Certainly in IDLE, when one hits a show() in a def, the program does not continue to the next statement. It goes somewhere else, because my program continues normally. Apparently, it goes back up the def calls to the "main" program, which is a loop that just reads the next file to perform more of what I expect. If I know this to be true*, that allows a "workaround" with globals.
* There is another def that uses plot-show, and it continues without any notable difficulty. The show() is the last statement in the def. Of course, since show() is a legitimate use, if one knows the "end" rule, this seems quite reasonable way to operate.
"Crime is way down. War is declining. And that's far from the good news." -- Steven Pinker (and other sources) Why is this true, but yet the media says otherwise? The media knows very well how to manipulate us (see limbic, emotion, $$). -- WTW